A particular concern in the event of a hypothetical
severe accident is the potential release of highly
radiotoxic fission product (FP) isotopes of ruthenium.
The highest risk for a large quantity of these isotopes
to reach the containment arises from air ingress
following vessel melt through. One work package (WP) of
the SARNET Source Term topic is producing and
synthesizing information on ruthenium release and
transport with the aim of validating or improving the
corresponding modelling of the ASTEC code. The WP
includes reactor scenario studies that can be used to
define conditions of new experiments.
The experimental database currently being reviewed
includes the following programmes:
- AECL Experiments conducted on fission product release
in air; results are relevant to CANDU loss of end fitting
- VERCORS tests on FP release and transport conducted by
CEA in collaboration with IRSN and EDF; additional tests
may potentially be conducted in more oxidizing conditions
in the VERDON facility;
- RUSET tests by AEKI investigating ruthenium transport
with and without other FP simulants;
- Experiments by VTT on ruthenium transport and
speciation in highly oxidizing conditions.
In addition to the above, at IRSN and at ENEA modelling
of fission product release and of fuel oxidation is being
pursued, the latter being an essential boundary condition
influencing ruthenium release.
Reactor scenario studies have been carried out at INR,
EDF and IRSN: calculations of air ingress scenarios with
respectively SCDAP/RELAP5 and ICARE/CATHARE V2;
SATURNEMAAP; and ASTEC codes provided first insights of
thermal hydraulic conditions that the fuel may experience
after lower head vessel failure.
This paper summarizes the status of this work and plans
for the future.
|Title of host publication||Proceedings|
|Subtitle of host publication||2nd European Review Meeting on Severe Accident Research, ERMSAR 2007|
|Place of Publication||Karlsruhe|
|Publication status||Published - 2007|
|MoE publication type||A4 Article in a conference publication|
|Event||2nd European Review Meeting on Severe Accident Research, ERMSAR-2007 - Karlsruhe, Germany|
Duration: 12 Jun 2007 → 14 Jun 2007
|Conference||2nd European Review Meeting on Severe Accident Research, ERMSAR-2007|
|Period||12/06/07 → 14/06/07|